<template>
  <div id="home">
    <nav-bar class="home-nav"><div slot="center">购物街</div></nav-bar>
  <tab-control :titles="['流行','新款','精选']"
   @tabClick="tabClick"
    ref="toptabControl"
    class="tab-control" v-show="isTabFixed" />
  <scroll class="content" ref="scroll"
   :probe-type="3"
    @scroll="contentscroll" 
    :pull-up-load="true"
    @pullingUp="loadMore">
    <home-swiper :banners="banners" @swiperImageLoad="swiperImageLoad"/>
  <recommend-view :recommends="recommends"/>
  <feature-view/>
  <tab-control :titles="['流行','新款','精选']"
   @tabClick="tabClick"
    ref="tabControl"/>
  <goods-list :goods='showGoods'/>
  </scroll>
  <back-top @click.native="backClick" v-show="isShowBackTop"/>
  </div>
</template>

<script>
import NavBar from 'components/common/navbar/NavBar'
import TabControl from 'components/content/tabControl/TabControl'
import GoodsList from 'components/content/goods/GoodsList'
import Scroll from 'components/common/scroll/Scroll'
import BackTop from 'components/content/backTop/BackTop'



import {getHomeMultidata,getHomeGoods} from 'network/home'
import {debounce} from 'common/utils'


// import Swiper from 'components/common/swiper/Swiper'
// import SwiperItem from 'components/common/swiper/SwiperItem'
// import {Swiper, SwiperItem} from 'components/common/swiper'
import HomeSwiper from  './childComps/HomeSwiper'
import RecommendView from './childComps/RecommendView.vue'
import  FeatureView from './childComps/FeatureView.vue'







  export default {
    name: "Home",
     components:{
         NavBar,
         RecommendView,
         HomeSwiper,
         FeatureView,
         TabControl,
         GoodsList,
         Scroll,
          BackTop,
    },
    data(){
      return {
        banners:[],
        recommends:[],
        goods:{
          'pop' :{page:0,list:[]},
          'new' :{page:0,list:[]},
          'sell' :{page:0,list:[]}
        },
        currentType:'pop',
        isShowBackTop:false,
        tabOffsetTop:0,
        isTabFixed:false,
        saveY:0

      }
    },
    computed:{
      showGoods(){
        return this.goods[this.currentType].list
      },
    },
    activated(){
        this.$refs.scroll.scrollTo(0,this.saveY,0)
        this.$refs.scroll.refresh()
      },
      deactivated(){
        this.saveY = this.$refs.scroll.getScrollY()
      },
  
    created(){
      //1.请求多个数据
      this.getHomeMultidata()

      //2.请求商品数据
      this.getHomeGoods('pop')
      this.getHomeGoods('new')
      this.getHomeGoods('sell')
    },
    mounted() {
       //1.监听item中图片加载完成
       const refresh = debounce(this.$refs.scroll.refresh,50)
       this.$bus.$on('itemImageLoad',()=>{
        refresh()
      })
    },

    methods:{
      //事件监听相关的方法
    
      tabClick(index){
        switch(index){
          case 0:
            this.currentType = 'pop'
            break
          case 1:
            this.currentType = 'new'
            break
          case 2:
            this.currentType = 'sell'
            break
        }
        //两个tabControl保持一致
        this.$refs.toptabControl.currentType = index
        this.$refs.tabControl.currentType = index

      },
      backClick(){
        this.$refs.scroll.scrollTo(0,0)
      
      },
      contentscroll(position){
        //1.判断backTop是否显示
       this.isShowBackTop =  (-position.y) > 1000
       //决定tabControl是否吸顶(position:fixed)
       this.isTabFixed = (-position.y) > this.tabOffsetTop
      },
      loadMore(){
        // console.log('上拉加载更多!');
        this.getHomeGoods(this.currentType)

      },
      //吸顶效果
      swiperImageLoad(){
         //2.获取tabControl的offsettop
      //所有的组件都有一个属性$el:用于获取组件的
      this.tabOffsetTop = this.$refs.tabControl.$el.offsetTop;
      },


      // 网络请求相关的方法
      getHomeMultidata(){
         getHomeMultidata().then(res =>{
        // console.log(res);
        this.banners = res.data.banner.list;
        this.recommends = res.data.recommend.list;
      })
      },
      getHomeGoods(type){
        const page = this .goods[type].page + 1
        getHomeGoods(type,page).then(res => {
        this.goods[type].list.push(...res.data.list)
        this.goods[type].page += 1

      //完成上拉加载更多
      this.$refs.scroll.finishPullUp()
      })
      }
    }
  }
</script>

<style scoped>
#home {
  /* padding-top: 44px; */
  height: 100vh;
  position: relative;
}
  .home-nav{
     background-color: var(--color-tint);
     color: #fff;
  }
 
  .content {
    overflow: hidden;

    position: absolute;
    top: 44px;
    bottom: 49px;
    left: 0;
    right: 0;
  }
  .tab-control {
    position: relative;
    z-index: 9;
  }
</style>
